1. Field of the Invention
The present invention relates to an optical-electrical connector, and more particularly to an optical-electrical connector of SFP (Small Form-factor Pluggable) interface including a resilient member for providing a low loss optical coupling between the fibers and the lens member.
2. Description of Related Art
U.S. Pat. No. 7,794,156 issued to Wang et al. on Sep. 14, 2010, U.S. Pat. No. 7,581,891 issued to Wang on Sep. 1, 2009, and U.S. Pat. No. 7,401,985 issued to Aronson et al. on Jul. 22, 2008 each disclose an optical-electrical connector, i.e., an active optical connector or a transceiver. The optical-electrical connector includes a housing, a circuit board having a transducer, a lens member and a ferrule received in the housing, and a plurality of fibers mounted in the ferrule. The ferrule is aligned with the lens member so as to align the plurality of fibers with the lens member for optical signal transmission. The transducer is used for bidirectional optical-electrical signal communication.
It is important to align the ferrule with the lens member reliably; otherwise loss of optical coupling between the fibers and the lens member will result.
U.S. Pat. No. 5,214,730 issued to Nagasawa et al. on May 25, 1993 discloses two MPO (Multiple-Fiber Push-On) connectors. Each MPO connector includes a ferrule carrying a plurality of fibers, a coiled spring situated behind the ferrule, and a shell shrouding the ferrule and the spring. When the two MPO connectors mate with each other, the ferrules of the two MPO connectors are pressed against each other in an axial direction by the coil springs, so as to maintain the connected state under a proper alignment.
The coiled spring providing a resilient force to the ferrule has been used in MPO connector, but has not been applied in an optical-electrical connector of SFP interface. Additionally, the coiled spring would be compressed into different lengths for providing different resilient forces in the mating process.
U.S. Patent Application Publication No. 2011/0081119 published on Apr. 7, 2011 discloses a connector includes a housing, a paddle board received in the housing, a mounting plate vertically mounted on the paddle board, a lens block mounted in the mounting plate, a ferrule carrying a plurality of fibers, a package having an engaging portion engaged with the ferrule and a shoulder portion, a spring confined between the ferrule and the shoulder portion of the package, and a cover engaged with the package and the lens block. The ferrule is aligned with the lens block reliably under a resilient force provided by the spring.
The ferrule is aligned with the lens block and the spring is secured to the ferrule by the package and the cover. The connector has a complicated configuration to provide the package and the cover.
Hence, a differently configured optical-electrical connector having a resilient member is desired.